Peterson, a former Bolingbrook police sergeant, was charged only after his fourth wife, Stacy Peterson, disappeared in 2007. Prosecutors had no physical evidence and built a compelling circumstantial case -- one that lead jurors to conclude Peterson must have killed Savio.

Peterson is a suspect in Stacy's disappearance but hasn't been charged. He's pleaded not guilty to first-degree murder in Savio's death.

Peterson now faces a maximum prison sentence of 60 years. He'll be sentenced Nov. 26.

NBC Chicago has reporters in the Will County Courthouse for the trial. For an up-to-the-minute play-by-play during proceedings, follow @bjlutz on Twitter.